Casting press



Feb. 27, 1940.

H. FQ'HAGEMEYER 2,192,133

CASTING Pimss Filed Aug. 10, 1938.

INVENTOR.

HENRY F. HAGEMEYER.

Patented Feb. 27, 1940 UNITED: STATES ,PATENT OFFICE CASTING PRESS HenryF. Hagcmeyer, Chicago, Ill. Application August 10, 1938, Serial No.224,005

'1 Claims.

flask or mold form on one surface of which is mounted a pattern, in theregion of contact of the material with the flask sides a slight meniscuswill be formed, which will persist after the mold has set, causing aslightly raised rim on the .back thereof. Other irregularities may alsooccur from variations in the amount of shrinkage which takes place indifierent portions of the mold owing to differences in thickness of themold cavity 30 wall. In drying a slight warpage may occur whichalsotendstocreateanirregularsurface on the mold back.

Heretofore it has been conventional practice to press against the backof a mold section a rigid pressure plate which will not conform toirregularities on the engaged mold surface, and hence will produce anundesirable unequalized pressure on the fragile mold. I have devised apressure transmitting member incorporating a flexible 30 metal sheetwhich will contact a somewhat irregular surface in a yielding manner, sothat its engagement will be substantially contiguous over the entiremold surface andthe pressure will, therefore, be distributed over suchsurface in 85 a substantially uniform manner.

It is therefore a principal objective of my invention to provide amechanism to be used with a casting press for contingously enga anirregular mold surface, to distribute the pressure 40 uniformly oversuch surface.

A further object is to provide a mold engaging member which, whileyleldable to conform to irregularities of the mold surface, willnevertheless be heat resistant and of durable construction.

It is also an object to provide such a member which may be employed withthe conventional type of casting press, being adapted for insertionbetweenv a press plate and the back of the adjacent mold section.

Still another object is to provide controllable mechanism operable tovary the degree of flexing which may take place in the mold engagingmember for a given pressure exerted thereon.

' All these objects I obtain by a device of simple and compactstructure.

Other objects of my invention will be understood from the followingspecific description of the representative structure illustrated in thedrawing. The novel features of my device are defined particularly in theclaims.

Fig. 1 is a longitudinal central section through a press and assembledmold, with my pressure members in place above and below the mold andbetween the press plates.

Fig. 2 is a sectional view taken along line of Fig. 1. I

Fig. 3 is a top perspective view of a lower pressure member. I

Fig. 4 is a detail sectional view through a pressure control valve. 1

A representative mold including a cope section C and a drag section D isshown in Fig. 1 disposed between an upper press plate I and a lowerpress plate III of a conventional casting press. Plunger 3, carried by apiston reciprocable in a conventional fluid pressure cylinder- (notshown) may be employed as the pressure creating mechanism. Between eachof the press plates 1 and Ill and the adjacent mold section is disposeda pressure transmitting member, generally indicated as 2.

The surfaces of members 2 which engage the backs of mold sections C andD'are thin metal sheets 20. These sheets are sufliciently flexible toengage contiguously the mold backs even though they have a considerablemeniscus or other irregularities. In addition to the flexible moldengaging sheet, each pressure transmitting memher 2 includes a secondsheet 2|, which may or may not be flexible, to be engaged by a press 85plate. A simple construction may comprise two complemental sheets of thesame shape and size with Offset edges which may be placed in abutmentand secured together to form a seam 22, while the central portions ofthe sheet are held in 40 spaced relation. Since sheet 2| seats flatagainst the plane surface of a press plate it may be of the same gaugeas shee 20, the flexibility here being neither of advantage or adisadvantage, and the equal thickness simplifying fabrication byallowing the seam 22 to be welded or brazed readily without overheatingthe edge of one member, asmight occur with stock of diffeerentthicknesses.

In order to vary the flexibility of the mold engaging sheets, the fluidpressure in the hollow between the central portions of the two sheetsmay be altered. The operation may be accomplished by providing apressure relief .valve 4 of any conventional construction, arepresentative valve behand the greater the pressure to 115g illustratedin Fig. 4, located in the'discharge conduit from this pressure member.The pressure at which this valve releases fluid from the hollow membermay be adjusted according to the fluid can be supplied to the pressuremember to increase its internal pressure, such conduit being positivelyclosed when the pressure has been adjusted .to that desired. Generallythe greater the irregularity of the mold back, the greater should be theinternal pressure. On the other be exerted on the mold, the greatershould be the pressure within the pressure member so that the thinsheets thereof will not be subjected to excessive stress.

The pressure member 2 which is shown in Fig. 3 Would'ordinarily beemployed between a lower press plate l0 and the back of the mold drag.Such a member cannot conveniently be employed between the upper pressplate I andthe back of the cope C because a sprue 'S is ordinarilyprovided into which the metal is poured to flow through the gate G intothe casting cavity. While the same general type of pressure member maybe used for the cope, a cutout 25 should be provided in it as shown inFig. 2, through which the sprue 5 may project. Preferably this reentrantportion, 25 extends back beyond the connection of the gate G with themold cavity, so that the metal in the sprue and gate will not be cooledat an excessively rapid rate-by fluid flowing through the hollow of thepressure member.

If desired the inlet, conduit 23 may be connected with the right end ofthe upper pressure member but such connection would necessitate twooutlet connections 24, one for each bifurcation formed by the cutout 25.A single outlet only need be used, however, if the inlet is connected toone bifurcation and the outlet to the other, as illustrated in Fig. 2.While I have shown the inlet for the lower pressure member connected tothe end thereof remote from the sprue S and gate G, such disposition isunimportant in the maintenance of the desired pressure within thepressure member. In fact such connections may be located at any pointalong the edge, it being unnecessary that the inlet and outlet'beconnected to opposite sides. Such disposition of the connections isadvantageous, however, for controlling the cooling of metal in thecasting cavity according to the method disclosed in my companionapplication, Serial No. 222,599, filed Aug. 2, 1938, for Mold coolingmethods and apparatus.

When my pressure members are employed between the plates of a press anda mold, and the pressure in such members has been adjusted according tothe degree of irregularity of the mold back and the pressure to beexerted on the mold surfaces, an even pressure over such surfaces isobtained which will not set up unequal strains in a fragile mold such asone of the gypsum base type. The pressure between the parting surfacesof the mold sections will be substantially evenly distributed, thusforming a tight seal about the mold edges, preventing the metal breakingthrough thejunction of the parting surfaces when it is poured into themold cavity, and tending to two parallel, thin,

prevent the formation of undesired fins on the v casting.

The fluid used in the pressure members is preferably oil, although itmay be water, oreven compressed air or other compressed gas.

By the expression surface of a mold member used in the claims I mean anysurface of the -mold assembly engaged by my pressure mem ber which isirregular, either'by reason of its method of fabrication, from treatmentit receives thereafter, or from its method of use. .Thus, for example, amold covering, having an irregular surface by conforming to an irregularsurface of a cope or a drag, or itself having an irregular surface,engaged by the pressure member, is an element of the mold assembly andwould be included within the term mold member.

I claim as my invention: v

1 Apparatus for clamping together complementary mold members for thepouring operation, comprising pressure creating means, and an all-metalpressure member having one side engaged by said pressure creating means,and including on the other side thereof a thin, flexible metal sheetengageable directly with a surface of a. mold member and deformable toconform substantially to the irregularities in such mold surface and todistribute substantially uniformly over such irregular mold surface thepres sure exerted on said pressure member by said pressure creatingmeans.

2. Apparatus for clamping together complementary moZd members for thepouring operation,

surface of a mold member, and deformable to conform substantially to theirregularities in such mold surface and to distribute substantiallyuniformly over such irregular mold surface the pressure exerted on .saidpressuremember by said pressure creating means.

3. The combination of claim 2 and means connected to the hollow,fluid-filled, pressure member operable to remove fluid from. suchpressure member or to supply additional fluid thereto to vary theinternal pressure thereon 4. Apparatus for clamping togethercomplementary mold members for the pouring operation, comprisingpressure creating means, and a hollow, fluid-filled, pressure memberformed of flexible metal sheets having their edges joined together, onesheet being engageable over substantially its entire area by saidpressure creating means, and the other sheet being engageable directlywith a surface of a mold member and deformable to conform substantiallyto the irregularities in such mold surface and to distributesubstantially uniformly over such ir egular mold surface the pressureexerted on said pressure member by said pressure creating means.

5. Apparatus for clamping complementary mold members against each otherfor the pouring opeld firmly in contact with each other around themoldcavity, said hollow member yielding un equally as necessary indifferent parts thereof to compensate for faults in the mold members. a

6. Apparatus for clamping complementary mold members against each otherfor the pouring operation, which apparatus comprises a memberineluding aflexible sheet of metal, and means acting through said flexible sheet ofmetal for forcing the mold members against each other to have theparting surfaces thereof held firmly in contact with each other aroundthe mold cavity, said flexible sheet of metal yielding unequally asnecessary in diiferent parts thereof to compensate for faults in themold members.

'7. Apparatus for clamping together complementary mold members for thepouring operation, comprising pressure creating means, and a hollow,liquid-filled, sealed, pressure member flexible sheet wall.

normally of uniform thickness and having parallel planar opposite walls,one of said walls including a thin, flexible sheet engageable directlywith a surface of a mold member, and deformable under the stress exertedby said pressure creating means to conform substantially to theirregularities in such mold surface, and to distribute' substantiallyuniformly over such irregular mold surface the pressure exerted on saidpressure member by said pressure creating means, said pressure membervarying in thickness under such stress as required by deformation ofsaid HENRY F. momma.

